WEAK CAPTURE OF PROTONS BY PROTONS

The cross section for the proton weak capture reaction H-1(p,e(+) nu(e ))H-2 is calculated with wave functions obtained from a number of mode rn, realistic high-precision interactions. To minimize the uncertainty in the axial two-body current operator, its matrix element has been a djusted to reproduce the measured Gamow-Teller matrix element of triti um p decay in model calculations using trinucleon wave functions from these interactions. A thorough analysis of the ambiguities that this p rocedure introduces in evaluating the two-body current contribution to the pp capture is given. Its inherent model dependence is in fact fou nd to be very weak. The overlap integral Lambda(2)(E = 0) for the pp c apture is predicted to be in the range 7.05-7.06, including the axial two-body current contribution, for all interactions considered.